A wheel bearing joint unit of said type is described in DE 36 36 243 A1. The screw element is generally a bolt with a head and with a thread on a shank. The head of the bolt bears flat, in a screwed fashion, with a generally vertical planar contact face against a correspondingly vertical planar support face of the hub. The joint component is for example the bell of a constant-velocity joint. Formed in the base of the joint component or in a corresponding extension of the joint component is an internal thread.
During the assembly of the unit, the bolt is guided by means of the shank through a corresponding passage hole in the hub and screwed into the internal thread. The connection by means of the toothings is generally highly axially loaded by the screwing of the elements. The high forces lead to deformations in the screw connection.
The base of the joint component is therefore deformed in the direction of the head of the screw element. The deformations on the joint component under some circumstances adversely affect the position and shape of the joint component. Plastic or elastic deformations on the thread or on the surroundings of the thread are transmitted to the toothing and adversely affect the engagement.
During the screwing process, the head of the bolt is pulled into the passage hole axially in the direction of the thread. The planar contact face of the bolt on the support face is deformed into the shape of a “plate” and rises up from the support face on the flange. The bolt bears against the chamfer or edge which delimits the support face from the passage hole. As a result, the hub and the head are then in contact only by means of edge contact. The head is pulled in all the more the greater the radial spacing between the shank and the inner wall of the passage hole. Non-uniform distributions of stresses in the material of the screw connection and its surroundings can lead to a decrease in the axial preload and to damaging stress peaks in the connection. Dirt and water pass into the annular wedge between the contact face and support face.